The corticosteroid nasal spray will squash the sinus inflammation in the short term. But, it will promote Th2 dominance longterm. We know that Th2 dominance drives candida overgrowth and chronic inflammation. Cortisol induces apoptosis of Th1 cells and NK (natural killer) cells, so whatever bacteria you have in your sinuses will love this direction your going in and as soon as the steroid is stopped, the bacterial sinusitis will come roaring back. Not always, but so often that it’s likely the steroid is a poor maneuver.